Summoning Sciences
by Hrodvitnon
Summary: [elsannonymous fill; G!P] In which Anna unwittingly summons a centuries-old demon with something of a history with her family.


Originally submitted to the elsannonymous Halloween-themed fillathon. Just so there's no confusion, as noted in _Hróðvitnir_ I'm the original author behind this. I know there was someone posting some elsannonymous fics a while ago, so... just throwing this out there.

 **Based on Prompt 8:** Witch Anna accidentally summons friendly ice demon Elsa.

 **Warnings:** Demon!Elsa, g!p Elsa, witch!Anna, Anna is a power bottom, master and servant relationship, dry humping (tail humping?), biting, temperature play, dream sex, creature sex, rough sex, references to Irish folklore, tw: blood and violence (in flashback).

* * *

Let it be known that regardless of the progresses in technology or the advances in science, magic is indeed still an Actual-And-Accounted-For practice. There are just as many forms of magic, and by proxy practitioners of it, as there are races and cultures in the world. Many people will label them as good or evil, but Anna's of the opinion that magic belongs in a more morally gray area; with the exception of blood magic it's not _inherently_ bad or good, it all just depends on your intentions.

(Then again, Anna's only recently graduated from being an apprentice witch and is just now stretching her metaphorical wings.)

She's always been particularly interested in conjuration and the intervention of spirits and the like. Just what fonts of arcane knowledge can be gleaned by calling forth an entity from some alternate dimension, or plane of existence? Just the idea of learning something new about a familiar concept from a nonhuman creature makes Anna bounce on her heels in delight!

…Unless of course that arcane knowledge involves cosmic horror stories. Or tentacles. She's started reading Lovecraft _way_ too recently for that to be _any_ kind of okay.

So here Anna is, living alone in a decently-sized house with a lovely view of the fjord and forty acres of land, the closest neighbors being at least a mile away. Thank goodness too, because heaven forbid someone should be nosy enough to call on her in the middle of summoning sciences. It's taken long and arduous research into demonology and/or what spirits she might be dealing with (Anna has no intention of making Faustian deals this soon in her witching career) before coming across something in an ancient moth-eaten tome that must've belonged to a long-dead relative. She opens it gingerly, wincing when the spine cracks in protest.

Within is a symbol that, while similar to many, is unfamiliar to her. It resembles a snowflake with six main points and six secondary ones. Circling it is a foreign script, which a Google search tells her is called Ogham, an alphabet used to write the early Irish language. Anna glances at the symbol and bites her lip, conflicted. Naïve as she might seem, things like the Fair Folk or other mythical creatures found in Ireland rank pretty high on her list of Things to Not Ever Fuck With, For the Love of God.

This can either go fairly well or really, extensively, _horrifically_ bad.

 _It might be the wrong decision, but fuck it, it's mine._

She kisses the protective amulet around her neck and gets to work.

First the circle itself; next the twelve-pointed snowflake; and here, using the circle as a template, Anna takes great pains in writing out the Ogham inscription as accurately as possible. (You ever try writing in a dead alphabet you've never needed to use let alone heard about?) Finally candles are placed on the twelve points and lit. She flips the tome open again in case the summoning circle requires a sacrifice of some kind, hopefully just a bit of gold or a teensy drop of blood. You never know with these obscure spirits-slash-demons.

Anna blinks and tilts her head in slight surprise at the notes. No offering of material possessions or bodily fluid is necessary here ( _awesome!_ )— just reciting the entity's True Name. ( _…less awesome!_ )

Anna's no fool. Any third-rate cheap-jack entertainer of a magician knows that True Names (capitals required) have some of the oldest and most powerful magic. The names given to people by their families naturally have meanings and often describe _who_ they are as a person. By that token, True Names describe _what_ something is, describe its essential nature. To know the name is to know the thing; to speak the Name is to conjure by it. And don't think that just because the conjurer can influence its thrall doesn't mean the thrall can't influence the conjurer.

 _You know, the more I think about this the less sure I get. Oh, well._

Heart in her throat, the witch memorizes the Name written in her tome (looking to Google again for the proper pronunciation), and kneels before the completed circle in the center of her work room. Something _thrums_ from the snowflake's center.

 _—In it the Dark One was and twelve idols of stone around him and he himself of gold—_

" _ **Crom Dubh.**_ "

* * *

If one were to ask a demon what it's like to be summoned into the mortal plane, the closest analog one would receive is the sensation of being shrunken down and shot out of a cannon, but try to imagine that the cannon's trajectory is parallel lines that _intersect_ , and the first time it happens it feels like you're being torn asunder at the molecular level (or demonic equivalent) and the cannon is shooting you out two ways simultaneously.

Because, let's face it, no two dimensions are precisely the same and the Warp— or, the space that connects the dimensions— is a scary, _scary_ place. A demon entering the mortal plane is kind of like an astronaut walking on the moon or a robot exploring the depths of the Mariana trench. Of course the arrival is going to come with a bit of sensory overload, especially if whatever's taking the trip hasn't gone out in a while.

"OH, SHIT! OH, FUCK!"

The sudden shriek does _nothing_ to help the overwhelming sensation of coming into the material plane.

The room is spinning, her head is swimming, bones (oh right, that's a thing here) are like jelly, it feels like someone's pressing a spoon against the inside of her eye, and _Jaysus_ but it's been _so long_ since her last jaunt… fortunately, the wave of nausea passes. Once accustomed to the physical, the demon takes a look around.

Her surroundings appear to be a work room of some kind. It's not a bad size; there's a wardrobe and a tall mirror, the shelves are all occupied by books or ingredients, jars adorning one table while a smaller adjacent one is home to beakers and hot plates and a mortar and pestle, a desk littered with scrolls and books. Plus there's a weird… slim metal-looking thing connected to the wall with a blinking blue light on it. What's the word for that again…?

A loud shuffling grabs her attention. It's coming from that wardrobe. There's a muffled hitching of breath, and the demon realizes that she must have scared the bejeezus out of her poor conjurer.

"Hello."

The greeting sounds strange even to the demon's own ears, considering the flanging in her voice.

"…h-hello?" comes the uncertain reply.

"I didn't mean to scare you," the demon continues. From inside the wardrobe, Anna can detect some trace of a northern Irish accent. "You okay in there?"

"Uh, y-yeah, I'm fine! Minor heart attack and screaming aside, I'm fine!"

She smiles. "Good. Now I can meet my new master."

A beat.

"Your— wait, _what_?!"

"My new master… the witch who summoned me, as in you."

"I didn't see anything about being master to a demon in the book!" Anna half-shouts.

The demon glances around. "Which book do you mean?"

"The one that looks like it came from a crypt!"

Eyes as blue as a frozen tundra scan the room before spying the tome in question, lying open beside the summoning circle. Reaching out a draconic arm she jabs a claw at the yellowed paper, skimming through the words.

The demon calls out, "Says here under the recital of my True Name that I am bound to you and sworn to your services until death or the time you release me."

Another beat.

What comes out of the wardrobe is an embarrassed, "Oh."

"You know, if we're going to have a conversation, I'd much prefer speaking face-to-face."

"But how do I know you're just lulling me into a false sense of security so you can… I don't know, possess my body and do whatever you want with me?"

"Is that what you really think will happen?" the demon keeps her voice soft and playful. "That bit I just told you about is my geis— my vow. I must serve any witch of your bloodline who conjures by my Name, so if I violate that vow I'm… well, I'm dead where I stand. But if it really bothers you so much you're more than welcome to dismiss me."

…

"It's your decision, no one else's. There's nothing in this life but mist, eh little witch?"

Anna considers this. So far the creature seems inordinately nice as far as demons go, and she's even bound by a geis apparently.

 _…eh, what the hell?_ She kicks the wardrobe open and steps out.

Her heart _stops_.

Anna doesn't know what she expected to pull out of the ether, but she certainly hadn't expected it to be a demon with a geis associated with her family line, and definitely not one that shared the name of a Celtic wizard or deity; and no way in Hell or Hogwarts did she anticipate it to be one beauty of a demon.

The creature in her work room, peering curiously at the large collection of glass jars, vaguely reminds Anna of the Nāga (or _nāgiṇī_ in this case) in Hinduism; above the waist is a pale, gorgeous woman with windswept platinum-blonde hair and startlingly icy blue eyes. Her ears are slightly pointed, her forearms ending in draconic claws, dorsal spines line the snakelike tail taking up the lower parts of her, and all around that lean but muscled body are glacial protrusions like scales.

"Hi," the demon greets, waving.

Maybe the summoning took a lot out of her, or it could be how the demon nonchalantly talks to her like they're old friends, or perhaps it's the fact that _oh dear God the demon under my thrall is hot AND topless_ , but whatever the reason Anna's eyes roll back and she faints dead away.

The demon quirks an eyebrow and closes her raised hand. Not exactly the best first day with a new master, but it's certainly not the worst she's had either.

She idly makes a popping noise with her lips and says to nobody in particular, "Welp."

* * *

When Anna opens her eyes she knows she's dreaming, because last time she checked there wasn't a circle of standing stones anywhere near her home, there wasn't a full moon on Halloween in who knows how long, mist doesn't appear indoors, and it wasn't nighttime when she summoned the—

Oh, yeah. Where _was_ she, anyway?

Right on cue, a familiar face peers down at her and smiles charmingly.

"Hoo-hoo," the demon croons, wiggling her claws in a cute little wave. "Nice moon out, eh?"

"I'm dreaming," Anna demonstrates her unflagging devotion to the apparent.

"Ya don't say."

"What just happened?"

"You passed out, love." The demon gives her a coquettish look. "I must've made quite the first impression on you, _Master_."

 _Oh, boy._ Anna bites her lip, trying to ignore the fluttering in her stomach. She's about to speak when the demon shushes her lips closes with a finger.

"I know, you summoned me in the hopes of getting a different perspective on magic. So I thought, considering your current state of consciousness or lack thereof, why not start out with dreams? Oh, don't look at me like that. I didn't go _too_ deep into your head."

"You still looked into my head!" Anna accuses.

"If I went any deeper you'd know it. Ask me something only you would know; anything."

Anna rifles through her memories and, picking from as far back as she can remember, points at a spot on her head. "How did I get a concussion when I was five?"

"I don't know, how did you?"

Anna stares. The demon stares back, rolling her eyes.

"I'm a demon. I'm not _rude_."

"Good to know," Anna deadpans. "So why the change in scenery?"

"It's Samhain eve, no? I thought it was appropriate; almost reminds me of home." There's a flash of wistfulness in the demon's eyes. "I'd like you to call me Elsa, by the way."

Anna furrows her brow in puzzlement. "Why not go by Crom?"

Elsa's face hardens, her eyes reminding Anna of a snake. "Because that's not the Name I chose. It was given to me at a desperate time. This is much more practical."

Makes sense, considering. It wouldn't do either of them any good if someone else were to learn Elsa's True Name.

"So what happens now, Elsa?" Anna asks, testing the name on her tongue.

"Now we get started with the learning."

Elsa offers her hand and Anna takes it, being lifted to her feet with startling strength. By now Anna can smell the crisp air of autumn, feel the dampness of dew on her jeans; she approaches one of the standing stones around them and runs a hand down its ancient surface. Anna looks upward and beholds a sky full of blossoming nebulae and countless stars dotting the sky like millions of diamond shards. And beyond the stones and shrouded by mist, Anna realizes they must be somewhere on a mountain. She's never had a dream quite like this… could it be a reaction to Elsa's presence?

"That's one way of looking at it," says Elsa from behind Anna, making her jump. "Sorry. You wear your thoughts on your sleeve."

"Better than my heart, I guess."

"Smart girl. You've got one hell of an imagination, Anna. Everything we see here—" Elsa makes a grand, sweeping gesture with her arm, "is thanks to you. Come here, take a look at this."

Elsa slithers to the crumbled remains of a center standing stone and Anna follows. Her eyes watch as crystalline claws trace Ogham inscriptions carved into the fallen megalith. She instantly recognizes it as the same script used in the summoning circle. Getting an idea, she scans the remaining stones around them, counting…

 _—In it the Dark One was and twelve idols of stone around him and he himself of gold—_

"You're _good_ ," Elsa sounds genuinely impressed. Enthralled, even; but that may just be wishful thinking on Anna's part. "Even better than your ancestors were. In my experience, not many witches can recreate places and memories on this scale. Em, no pun intended." Her tail twitches, and it even strikes Anna as a little funny.

Once her chuckles subside though, Anna frowns. "But I've never been to a place like this…"

"That's the thing, love." Elsa grips Anna's shoulder with a firm but gentle hand. "When a witch has someone in her thrall, it doesn't have to be _her_ memories; they share a connection."

"So if you could take a peek into mine…" Anna trails off a little.

"Hey, it's only fair."

Anna bites her lip, looking both nervous and embarrassed. "But how do I…? I mean, I've never done this before…"

 _Oh, don't make it sound so tawdry._

If Elsa catches that last thought she doesn't show it. But that way the corner of her mouth quirks up indicates otherwise, and Anna's heart skips one or three beats when cold hands cup her cheeks, bringing her face close enough for their brows to bump together.

Blue locks onto teal and Anna finds that, even if she possessed the willpower, she wouldn't look away.

Elsa whispers, "Relax. Close your eyes."

She does, and it's like opening a floodgate.

The best way Anna can describe it as watching a series of mental snapshots flash rapidly in and out of her vision, but without the subconscious protection granted by frames or a camera screen; all of them brimming with colors, tastes, sounds, sensations—

Blood on the snow-covered plain.

Flesh against flesh— the most primal and erotic of unions.

Fire and steel; raids by Nordic invaders.

A collection of ingredients; clicking from a mortar and pestle.

A smiling man; a father? a friend?

 _"Ár nAthair, atá ar neamh—"_

Unforgiving cold.

A little girl laughing— "Do the magic!"

A High King illuminated by the rising sun.

A scream, a roar, a cry, the wails of innumerable souls—

( _The pagans held on to their faith even after Crom Cruach's death by a Christian hammer, but they needed a symbol to maintain that faith. The way their tired, broken faces just_ lit up _when they witnessed the very spirit of winter harnessed by something as small as a little girl who didn't know any better…_

( _So they called Elsa their god. They gave her the Name._

( _They were_ so happy.)

 _Too much it's not right not right it hurts make it stop too much it's **TOO MUCH**_

"MASTER! ANNA!"

Anna regains her senses and finds Elsa is holding on to her for dear life, shaking her slightly. In spite of the scales and claws and snake's tail and the wicked fangs, Elsa's eyes are damnably _human_.

The clues come together to form a whole; a millennia-old druid who would be made a deity, given the Name of the Dark One. Then, defeated by a god— a _real_ god, child of the goddess Danu— placed under a geis by mortals of Anna's blood for a thousand years and counting, but for what reason? Repentance? Punishment?

 _So you know me for what I am, or was._ Elsa doesn't seem to be concealing her thoughts. _For the blood is the life, the currency of the soul, the medium to transfer life. To take the blood of another is to take the essence of a soul into oneself._

"Master?" Elsa breathes.

Anna's spine tingles. She likes hearing that word too much, _far too much_ for her own good. Something within her says, _kiss her_. She ignores it.

"That was—" Anna's voice comes out hoarse, so she clears her throat and tries again. "T-That…"

"Was unexpected," Elsa finishes. "I'm not sure what happened. You should've only gotten only one memory."

"Well, I _am_ dreaming," Anna reasons. "Dreams are weird like that."

Elsa chuckles low in her throat, bumping their heads together. "That they are, love."

Anna sighs and doesn't resist the urge to run her fingers through Elsa's impressive mane. Only just now Anna notices that her thrall's massive tail has curled protectively around them, pressing their bodies together. Her mouth dries. _You are way too nice to be a demon,_ she thinks.

 _It helps remind me that I was human, once._

"So why were you placed under the geis?" Anna asks, hoping to distract herself from the way those scales rub _just right_ against her, even through layers of clothing.

Again Elsa looks wistful. "Funnily enough, it wasn't because of the lives offered to me by pagans. It's because of the one time I felt a shred of human decency and spared an ignorant child who wandered into Magh Slécht. Just a scared, lonely little girl; what was she doing wandering into my domain, I thought? Why was she alone when she must be protected at all cost from those who would destroy such a small creature? …how many small creatures like her had _I_ destroyed?"

"Elsa…"

"I could've killed her and made a sacrifice to ensure the harvest. It would have been so easy… but I didn't. I was kind, for once in my life, and let her go. So after she came back with her family and found me nearly dead…"

( _A High King of the_ _Tuatha Dé Danann_ _arrives at_ _Magh Slécht_ _and the Bringer of Famine greets him. A duel between Lugh and Crom Dubh; between a god and a dark sorcerer, it is no contest._

( _A shattered howl sounds with the break of dawn as Lugh's spear finds its target. The Dark Crooked One lies broken and defeated with pierced skin and severed spine, the spearhead greedily drinking the blood of Crom and countless sacrifices._ )

Elsa separates them enough for Anna to see: just below her sternum is a large, faded scar. Elsa twists herself around to show an identical one directly on her spine. It's a constant reminder of Crom's defeat, brought by the spear of Lugh.

"Oh God, Elsa!" Anna gasps.

"Naturally, I couldn't walk anymore. I think the girl's mother must have been a faerie wife, seeing as the hag put her geis on me and gave me my tail. I am to serve all the witches of her bloodline till it runs out, and only then can I rest easy…"

This time Anna initiates an embrace and Elsa's tail instinctively tightens around them. She places a feather-light kiss on Elsa's cheekbone, wisps of whitish hair tickling her face. Elsa hums contentedly.

"Trying to make me feel better?"

"Oh hush, you love it," Anna teases and punctuates it with a firmer kiss, this time above the eyebrow. She almost doesn't notice Elsa's arm wrapping around her waist. Anna continues with butterfly kisses on Elsa's near unnoticeable freckles.

Unexpectedly, Elsa turns her face at just the right time and their lips meet. They blink owlishly at each other until Anna closes her eyes and loses herself.

So _good_.

Something _hard_ presses against Anna's thigh and though she jerks slightly in response, she reminds herself that Elsa was Named after a _male_ god and while top half of her is feminine the rest of her doesn't have to be. What's more, it's actually quite the turn-on.

"Dirty girl," Elsa murmurs against her lips.

 _I'll show you dirty_ Anna decides and sharply pulls at Elsa's hair. The blonde hisses through clenched teeth at the motion, baring her fangs in a way that fuels the heat between Anna's legs. The witch has to remind herself she's dreaming and wills the layer of clothes gone, moaning at the feel of cold scales against her now bare skin.

"Give me your tail," she orders, nipping at the demon's exposed throat.

Elsa sighs and thrusts lightly against her. "Yes, Master."

While Anna maneuvers herself to turn around Elsa loosens the coils enough for the tip of her long tail to slip through, carefully ensuring that the smooth underside faces up. Anna grips the tail and pulls, rubbing the underside against her slick, aching folds. She moans throatily at the friction, grinding against it, lolling her head back to rest against Elsa's shoulder.

Elsa's hardness unsheathes and she ruts against Anna's shapely ass, breathing heavily, but not making any attempt to penetrate. Anna nearly shrieks when cold hands reach around and cup her breasts, arching hard into both the palms and tail doing the most _delicious_ things to her. She rolls her hips harder, faster, soaking the tail with her wetness.

Claws at her breasts, forked tongue on her neck, teeth at her ear—

"Say it." Elsa thrums and her tail coils tighter around them, bringing them closer together. "Say my True Name. _Command me, my Master!_ "

" _Crom Dubh,_ " Anna breathes into the pointed ear, relishing the shuddering, animalistic growl it elicits, how its bass reverberates in her very marrow. "You will take your monster cock—"

Her left hand, still in the coils, reaches back and firmly grips the heavy, rock-hard shaft, too thick for her entire hand to wrap around—

"You will bend your Master over this golden idol—"

A low, flanging groan in her ears—

"You will fuck your Master's tight little pussy so hard I will feel you in the waking world."

" _Master,_ " Elsa rumbles, drunk on lust. She snarls and bares white fangs when Anna squeezes and pumps her length. " _Yesss…_ "

"Obey!" Anna commands and sinks her teeth into the exposed neck.

" _Fuck!_ "

Before Anna can register it she's now lying on her back against the crumbled pillar, Elsa taking her left breast into her hot, _hot_ mouth, suckling hard on the nipple, and using her chilled hand to play with the right, grinding her thick cock against Anna's pussy. The juxtaposition of hot and cold on her chest is doing wonders, and Anna all but _screeches_ her praises and orders to the stars.

" _Yes_ , Elsa, _fuck yes_ , take me, ruin me, breed me _use me fuck me_ —"

Finally, as commanded, Elsa flips Anna onto her stomach and flattens herself against the warm flesh slick with sweat; she pumps her erection once, twice, three times and guides it to push smoothly into Anna's heat, smiling wickedly at the keening that escapes Anna's mouth.

"Harder!" Anna orders, throwing an arm back and gripping Elsa's neck as best she can. "Give it to me. Make me feel you when I wake up."

" _Yes, Master_ ," Elsa growls. She pulls out just enough for the engorged, slightly pointed tip to tease Anna's entrance before snapping her hips like a serpent striking in ambush, pushing Anna forward with the strength of her thrust.

Anna just about forgets her own name the pleasure is so intense.

A strong arm wraps around her waist and pulls Anna up flush against Elsa's breasts, the free arm braced against the megalith so hard her claws are digging into the stone. Elsa runs her tongue along the junction of Anna's neck and shoulder, kissing and sucking and biting until the hand at her neck pulls her into a heated kiss. Elsa greedily swallows Anna's groans and cries as she doubles her speed, drilling into Anna with powerful thrusts, strong enough to make her ache but not enough to hurt.

It doesn't take long for either of them. The way Anna squeezes around her length reminds Elsa _how long_ since the last time she's been with a woman, and she lowers the hand on Anna's waist to her swollen clit, retracting the claws to pinch and rub, all the while pounding mercilessly against Anna's ass.

Anna arches her back to let loose a scream while Elsa roars her release and _erupts_.

The intensity of her orgasm nearly blinds Anna and she loses the strength to support herself. Fortunately she doesn't have to; Elsa gently pulls her back as they slump backwards onto the grass, claws brushing through her hair and words of a homely, folk-sounding tongue whispered into her ear. Anna grows weary as she comes down from her high and the dream fades, like breath in winter air, into the mist.

—-

 **Crom Cruach:** (Old Irish pronunciation /ˈkɾˠɔmˠ ˈkɾˠuəç/; modern Irish _Cromm Crúaich_ ) – A pre-Christian Celtic god whose name can mean " _Crooked, Bloody One,_ " he was probably a fertility god who provided good yields of milk and grain in exchange for a first-born sacrifice. His cult image was a golden idol surrounded by twelve bronze or stone pillars on Magh Slécht. His festival, _Dé Domhnaigh Crum-Dubh_ (Crom Dubh Sunday) was celebrated on the first Sunday in August.

 **Crom Dubh:** (roughly pronounced _CRUM DUV_ ) – Meaning " _Dark, Crooked One_ " or " _Dark Crom_ ," he was a folkloric figure based off of Crom Cruach in pre-Christian Ireland; a Lord of the Harvest or Bringer of Famine. Depending on the source, he was either a pagan wizard banished by Saint Brendan or an evil god slain by Lugh of the Tuatha Dé Danann. His stone image was preserved in Cloghane until its theft in 1993.

 **Geis:** (roughly pronounced _gesh_ ; plural _geasa_ ) – An idiosyncratic taboo, curse, or even a gift, similar to being under a vow or spell. Someone under a geis must maintain it, as violating the associated vow for any reason will result in dishonor or death. For example, Cú Chulainn was under two geis: he must not eat dog meat, and he must accept any food offered by a woman. When a hag offers him dog meat he has no choice but to eat it, which leads to his death.

 **Ogham:** (roughly, _oh-um_ ) – As mentioned, an Early Medieval alphabet used to write the early Irish language and later Old Irish. 400 surviving inscriptions can be found throughout Ireland and the Counties of Kerry, York, and Waterford, as well as Pembrokeshire in Wales. The etymology for ogham is unknown, but a possible source may be _og-úaim_ , meaning "point-seam".

 **Magh Slécht:** (pronounced _Maw shlaykht_ ) – A historic plain in Ireland, translated as "place of prostration," it was the center of worship for the cult image of Crom Cruach. High King Tigernmas and 4,000 of his men died while worshipping Crom on Samhain eve, 1413 BC; worship of Crom was ended in the 5th Century AD by Saint Patrick, who destroyed Crom's golden idol.

 **Samhain:** (pronounced _SAH-win_ ) – A Gaelic holiday that marked the harvest season's end and the beginning of winter, observed in Ireland, Scotland, and the Isle of Man. It was believed to be a time when spirits and fairies came into the world and souls of the dead would revisit their homes. Celebrations included feasting and folk plays, guising and going door-to-door reciting verses in exchange for food.


End file.
